static void
vips_interpolate_bicubic_class_init( VipsInterpolateBicubicClass *iclass )
{
VipsObjectClass *object_class = VIPS_OBJECT_CLASS( iclass );
VipsInterpolateClass *interpolate_class =
VIPS_INTERPOLATE_CLASS( iclass );
object_class->nickname = "bicubic";
object_class->description = _( "Bicubic interpolation (Catmull-Rom)" );
interpolate_class->interpolate = vips_interpolate_bicubic_interpolate;
interpolate_class->window_size = 4;
/* Build the tables of pre-computed coefficients.
*/
for( int x = 0; x < VIPS_TRANSFORM_SCALE + 1; x++ ) {
calculate_coefficients_catmull(
(float) x / VIPS_TRANSFORM_SCALE,
vips_bicubic_matrixf[x] );
for( int i = 0; i < 4; i++ )
vips_bicubic_matrixi[x][i] =
vips_bicubic_matrixf[x][i] *
VIPS_INTERPOLATE_SCALE;
}
}
/* Calculate a mask element.
*/
void
vips_reduce_make_mask( double *c, VipsKernel kernel, double shrink, double x )
{
switch( kernel ) {
case VIPS_KERNEL_NEAREST:
c[0] = 1.0;
break;
case VIPS_KERNEL_LINEAR:
c[0] = 1.0 - x;
c[1] = x;
break;
case VIPS_KERNEL_CUBIC:
calculate_coefficients_catmull( c, x );
break;
case VIPS_KERNEL_LANCZOS2:
calculate_coefficients_lanczos( c, 2, shrink, x );
break;
case VIPS_KERNEL_LANCZOS3:
calculate_coefficients_lanczos( c, 3, shrink, x );
break;
default:
g_assert_not_reached();
break;
}
}
static void inline
bicubic_notab( void *pout, const PEL *pin,
const int bands, const int lskip,
double x, double y )
{
T* restrict out = (T *) pout;
const T* restrict in = (T *) pin;
const int b1 = bands;
const int b2 = b1 + b1;
const int b3 = b1 + b2;
const int l1 = lskip / sizeof( T );
const int l2 = l1 + l1;
const int l3 = l1 + l2;
const int l1_plus_b1 = l1 + b1;
const int l1_plus_b2 = l1 + b2;
const int l1_plus_b3 = l1 + b3;
const int l2_plus_b1 = l2 + b1;
const int l2_plus_b2 = l2 + b2;
const int l2_plus_b3 = l2 + b3;
const int l3_plus_b1 = l3 + b1;
const int l3_plus_b2 = l3 + b2;
const int l3_plus_b3 = l3 + b3;
double cx[4];
double cy[4];
calculate_coefficients_catmull( x, cx );
calculate_coefficients_catmull( y, cy );
for( int z = 0; z < bands; z++ ) {
const T uno_one = in[0];
const T uno_two = in[b1];
const T uno_thr = in[b2];
const T uno_fou = in[b3];
const T dos_one = in[l1];
const T dos_two = in[l1_plus_b1];
const T dos_thr = in[l1_plus_b2];
const T dos_fou = in[l1_plus_b3];
const T tre_one = in[l2];
const T tre_two = in[l2_plus_b1];
const T tre_thr = in[l2_plus_b2];
const T tre_fou = in[l2_plus_b3];
const T qua_one = in[l3];
const T qua_two = in[l3_plus_b1];
const T qua_thr = in[l3_plus_b2];
const T qua_fou = in[l3_plus_b3];
const T bicubic = bicubic_float<T>(
uno_one, uno_two, uno_thr, uno_fou,
dos_one, dos_two, dos_thr, dos_fou,
tre_one, tre_two, tre_thr, tre_fou,
qua_one, qua_two, qua_thr, qua_fou,
cx, cy );
out[z] = bicubic;
in += 1;
}
}
